POWER SUPPLY, DISCHARGE LAMP LIGHTING APPARATUS AND LUMINAIRE

摘要

PURPOSE: To avoid the dying-out of a load when the load is put into an output regulation state. CONSTITUTION: A controller 17 increases the frequency of an oscillation signal all when the output DC voltage of a variable DC power supply 11 is increased and reduces the frequency of an oscillation signal all when the output DC voltage of the variable DC power supply 11 is reduced. A driver 19 supplies switching signals b11 and b12 by which FET's 13 and 14 are alternately turned on and off with a frequency the same as the frequency of the oscillation signal all to the gates of the FET's 13 and 14. With this constitution, when a discharge lamp 10 is lit with modulated light, as the output DC voltage of the DC power supply 11 is increased, the dying-out of a load can be avoided when the load is put into an output regulation state.